With the rapid development of computer technologies, Internet technologies and mobile Internet technologies, a growing number of users use various client applications (for example, social apps, electronic shopping apps, electronic payment apps, Internet banking apps) installed on terminal devices (for example, smart mobile phones, tablet computers, personal computers, notebook computers) to obtain various services. To guarantee the safety of users' personal information and assets, user authentication is required for the majority of the client applications. At present, user authentication is carried out by entering an account number, a password and/or a verification code by the user for most apps.
However, many users' personal privacy data (for example, account numbers registered on various websites, passwords, names, mobile phone numbers, ID card numbers) may be illegally obtained and used by underground industries, causing great safety concerns.